Induction transmitter



R. G. M KEE INDUCTION TRANSMITTER Filed June 19, 1922 flag mud Gil/917:6.

INVENTOR Patented Mar. 31, 1925.

ATENT ounce.

RAYMOND G. MCKEE, OF'DELHI, NEW YORK.

INDUCTION TRANSMITTER.

Application filed June 19, 1922. Serial No. 569,367.

ful Improvements in Induction Transmit ters, of which the following is a specification.

This invention relates to telephonic devices. -More particularly the invention relates t transmitters of the magnetic-induction type.

Some of the objects of the present invention are: To employ magnetic means for setting up a magnetic flux adjacent the V1- bratory diaphragm to obviatethe use of an electrical battery; to employ magnetizable element which is connected to the vibratory diaphragm so that the same mayyibrate therewith and means on the opposite side of the vibratory diaphragm for balancing the action of said magnetizable element; to provide means allowing the employment of electrical energy'for heavy work; and with these and other objects in view the invention resides in the particular provision, construction, relative disposition and operation of parts hereinafter fully described and illustrated in the accompanying drawing,

in which Figure 1 is a sectional view taken on a line centrally through the device.

Figures 2 and 3 are sectional views look ing in opposite directions from the line m-ze. 1

Referring now more particularly to the several views of the drawing for the details, it will be apparent that, the device of the present invention will include a shell 10 preferably of brass and open at one end. Arranged inside of the shell are magnets 11. Tihesc m: tsll are of the llOl'SO-SllOO type, each a relatively long and short leg '12 and 13 respectively. The magnets 11 are connected together in'pairs. The short legs 13 of one pair are riveted together as at 1 1-, whereas the short legs 13 of the other pair of magnets are riveted to the riveted short legs of the other pair of magnets. Each long leg 12 of each magnet is secured to the shell 10 by a screw 15. A vibratory thin steel diaphragm 16 is arranged transversely of the shell 10 the open end thereof, and the said diaphragm 5 lies against the ends of the long legs of the magnets "11 by virtue of which magnetism will flow through said dia-pragm. The shell is-internally screw threaded to receive the externally screw threaded flange of a cap 17. The flange of the cap 17 is brought into contacting relation with the diaphragm 16 to hold the same securely in place The I cap 17 is made preferably of brass and the same has a central screw threaded hole therein which accommodates the screw threaded end of a mouth-piece 18. In order that a magnetic flux may be set up by the short legs 13 of the magnets 11, there is employed a field-coil 19 which is carried by the said short legs 13. The field-coil 19 comprises a member 20 of iron, and windings 21 of copper wire. The member20 embodies a recessor pit 22 and a hole 23. There is a screw threaded bore 24: formed in the ends of the legs 13 to accommodate a screw 25 which is passed through the hole 23 in the attachment of the field-coil 19. In the assemblage of the field-coil 19 with respect to the diaphragm the field-coil is in position to readily receive the vibrations of whatever kind leaving the said diaphragm.

In order that the vibrations which are set up in the diaphragm may be amplified, and be rendered clear and smooth there is provided means in addition to the magnets 11 and the field-coil 19. The means comprises an armature coil 26 connected to one side of the diaphragm, and an element in the na-.

32 has a flange 33 and extending axially from said disk is a part 3 1 which acts as an.armaturc. The element 27 has a knob 35 at one end thereof which acts as a weight, and the opposite end of the element is screw threaded to accommodate nuts 36 and the nut 37. The diaphragm 16 has a hole in the axial center thereof which allows the elefment 2'; to be extended therethrough. The screw threaded end is screwed into the bore 30 with the nut 37 disposed between the disk 31 and the diaphragm, Whereas, the nuts 36 are disposed on the opposite side of the diaphragm to rigidly hold the parts as-i sembled. In the assemblage of the parts the armature 34 is disposed in the recess or pit 22, and the flange 33 surrounds the field-coil 19 to some extent,

From the foregoing it will be manifest that means is employed for setting up a magnetic flux in and about the diaphragm which renders the device very sensitive; that by employing a balanced armaturecoil on the diaphragm in conjunction with the field-coil and permanent magnets the diaphragm and armature-coil may be much further magnetized, with increased results in the field-coil, when the sound waves cause the diaphragm to vary the distance between the coils. This variation between the two coils'in efiect is similar to the effect of an alternating current generator on a very small scale.' The shell 10 is provided. with binding posts 38. There are preferably four binding posts. The ends of the windings 21 are connected to two of the binding posts which mitter of the present inventionmay belatter are also connected in the line. If desired,'to carry out heavy work, the ends of the windings 29 may be connected to a source of electrical energy by yirtueof' the other two bindingposts 38.

It should now be manifest that the transused for instance directly in an arc transmitting circuit. It may be used to render radio systems more thoroughly eificient because of its non-microphonic effects. device can also be perfectcd so that the use of a battery is obviated.

While there has been shown the preferred embodiment of the invention, it is to be understood that, changes, alterations and modificati n within the scopeof the claims hereunto appended may be resorted to wblienever it is deemed necessary or desira e. a

What is claimed is: 1. A telephonic device of the character described comprising a vibratory diaphragm, an armature coil carried by said diaphragm, a rocker excite-r passing through the diaphragm and having its innerend secured to the armature coil, a weight formed on the outer end. of the rocker excitcr to balance the armature coil and means for magnetizing said diaphragm and said armature coil respectively.

2. A telephonic device comprising a shell, a vibratory diaphragm held in place in said shell, permanent magnets arrangedat an angle with respect to said vibratory diaphragm, one pole of each of said permanent magnets touching said diaphragm, a field-coil, one pole of each of said permanent magnets touching said field-coil, a magnetizable element in magnetizable relation to said diaphragm, and an element con- The netizable element for balancing the action of saidmagnetizable element.

3. A telephonic device including a vibratory diaphragm, juxta-posed magnetic elements at one side of the diaphragm, one of said magnetic elements beingslightly larger than the other of said magnetic elements and having a portion overlying the latter element, means passing through said diaphragm and connected with the larger of said magnetic elements and supporting the same and connecting it with the diaphragm, and said means being weighted at the side of the diaphragm opposite that at which the magnetic elements are disposed, for bal ancing the action of said element connected to the diaphragm.

4. A telephonic tory diaphragm, juXta-posed magnetic elements at one side of said diaphragm, said magnetic elements being substantially in the shape of disks, one of said magnetic elements being of slightly greater diameter than the other of said elements, the larger of said elements having an annular flange "surrounding a portion of said smaller ele'-.

ment, means passing through said diaphragm and .connected with the larger of .said magnetic elements,and supporting the same and connecting it with the diaphragm, and said means being weighted at the side of the diaphragm, opposite that at which the magnetic elements are disposed, for balancing the action'v of said elements connected to the diaphragm.

device including a vibra- 5. An induction transmitter including a magnetized vibratory diaphragm, a magnetizable element at one'side of said diaphragm and connected thereto, and a field coil arranged adjacent said magnetizablc element,a weighted rocker cxciter passing through the diaphragm and associated with the field .coil as and forthe-purpose specified.

6. A telephonic device comprising a shell, a vibratory diaphragm held. in place in said shell, )ermanent magnets in the shell, one pole of each of said permanent magnets touching said diaphragm, a field coil, the other pole of each of said permanent magnets touching said field-coil, and an armature coil in magnetizable relation to said dia phragm, and a weighted rocker excitcr passing through the diaphragm and secured to the armature coil for balancing said armature coil with respect to the field coil and diaphragm.

7. A telephonic device comprising a shell, a vibratory diaphragm held in place in said shell, permanent magnets in the shell, one pole of each of said permanent niagnets touching said diaphragm, a field coil, the other pole of each of said permanent magnets touching said field coil, and anarmature coil disposed between said diaphragm and said field coil and in magnetizable relation to said diaphragm, and a Weighted exciter passing through the diaphragm and being secured to the armature coil.

8. A telephonic device comprising a shell, a vibratory diaphragm held in place in said shell, permanent magnets, one pole of each of said permanent magnets touching said diaphragm, a field coil, the other pole of each of said permanent magnets touching ,said field coil, an armature coil arranged between said diaphragm and field coil and in magnetizable relation to said diaphragm,

and an element connected to said diaphragm 15 In testimony whereof I hereby afiix my 20 signature.

RAYMOND G. MQKEE. 

